Detect dm-verity in kernel.

diff --git a/lib/libdevmapper.c b/lib/libdevmapper.c
index 0174f1f..4ec5abd 100644 (file)
--- a/lib/libdevmapper.c
+++ b/lib/libdevmapper.c
@@ -127,6 +127,16 @@ static void _dm_set_crypt_compat(const char *dm_version, unsigned crypt_maj,
                _dm_crypt_checked = 1;
 }
 
+static void _dm_set_verity_compat(const char *dm_version, unsigned verity_maj,
+                                  unsigned verity_min, unsigned verity_patch)
+{
+       if (verity_maj > 0)
+               _dm_crypt_flags |= DM_VERITY_SUPPORTED;
+
+       log_dbg("Detected dm-verity version %i.%i.%i.",
+               verity_maj, verity_min, verity_patch);
+}
+
 static int _dm_check_versions(void)
 {
        struct dm_task *dmt;
@@ -158,6 +168,11 @@ static int _dm_check_versions(void)
                                             (unsigned)target->version[0],
                                             (unsigned)target->version[1],
                                             (unsigned)target->version[2]);
+               } else if (!strcmp(DM_VERITY_TARGET, target->name)) {
+                       _dm_set_verity_compat(dm_version,
+                                            (unsigned)target->version[0],
+                                            (unsigned)target->version[1],
+                                            (unsigned)target->version[2]);
                }
                target = (struct dm_versions *)((char *) target + target->next);
        } while (last_target != target);

diff --git a/lib/utils_dm.h b/lib/utils_dm.h
index 85e0941..39fcf68 100644 (file)
--- a/lib/utils_dm.h
+++ b/lib/utils_dm.h
@@ -35,6 +35,7 @@ struct crypt_params_verity;
 #define DM_SECURE_SUPPORTED   (1 << 2) /* wipe (secure) buffer flag */
 #define DM_PLAIN64_SUPPORTED  (1 << 3) /* plain64 IV */
 #define DM_DISCARDS_SUPPORTED (1 << 4) /* discards/TRIM option is supported */
+#define DM_VERITY_SUPPORTED   (1 << 5) /* dm-verity target supported */
 uint32_t dm_flags(void);
 
 #define DM_ACTIVE_DEVICE       (1 << 0)

diff --git a/lib/verity/verity.c b/lib/verity/verity.c
index f66b9b9..0dd268f 100644 (file)
--- a/lib/verity/verity.c
+++ b/lib/verity/verity.c
@@ -190,6 +190,10 @@ int VERITY_activate(struct crypt_device *cd,
                return r;
 
        r = dm_create_verity(name, verity_hdr, &dmd);
+       if (!r && !(dm_flags() & DM_VERITY_SUPPORTED)) {
+               log_err(cd, _("Kernel doesn't support dm-verity mapping.\n"));
+               return -ENOTSUP;
+       }
        if (r < 0)
                return r;
 

diff --git a/src/veritysetup.c b/src/veritysetup.c
index 0abf5cc..de63c52 100644 (file)
--- a/src/veritysetup.c
+++ b/src/veritysetup.c
@@ -18,7 +18,6 @@
  */
 
 /* TODO:
- * - detect dm-verity (devmapper)
  * - init_by_name()
  * - unify units / uint64 etc
  * - check translations